He explains that California Democratic Rep. George Miller in 1992 led the first major water siege with the Central Valley Project Improvement Act, which allocated 1.2 million acre-feet of water to wildlife—enough to sustain 1.2 million families and 300,000 acres. The law aggravated the existing acrimony between farmers and environmentalists, and resulted in a turf war between federal and state regulators.

Eventually, green groups, farmers, the feds and state reached an armistice with the 1994 Bay Delta Accord, which jettisoned a demand by environmental groups to restore fish to a dry stretch of the San Joaquin River. Sen. Dianne Feinstein in October 1994 expressed her unequivocal opposition to "any effort to take water from Friant Dam for the purpose of restoring a long gone fishery on the San Joaquin River." Such a water diversion, she said, would have proved devastating to "10,000 small, family farms."

But environmental groups soon broke the peace by suing for more water diversions to protect salmon and smelt. By 2009, Ms. Feinstein's views had reversed: She backed the San Joaquin River Restoration Settlement Act, whose goal was to restore fish to what had been a dry river bed. But not just any fish—specifically, cold-water salmon that hadn't been documented at the site since the 1940s. Cold-water salmon require "huge volumes of water" to thrive, Mr. Watte notes, and he thinks that was exactly the point. The environmentalists "don't care about fish," he says. "The fish are just a prop, a vehicle to get our water." . . .

As an economist, I would charge everyone the same amount for water. But that is obviously not the case in California. The article notes:

An acre-foot of water (enough to submerge an acre of land in one foot of water) can cost up to $1,300 compared with about $40 a few years ago. Meanwhile, some farmers are drilling deeper wells at a cost of $1 million per hole. . . .